Vacuum lightning-arrester.



J. T. GREENE.

VACUUM LIGHTNING ARRESTER.

APPLICATION FILED 050.16, 1912.

1,191,69. Patented Jul 18, 1916.

WITNESSES:

UNITED STATES PATENT OFFICE.

JOHN TYLER GREENE, OF TOLEDO, OHIO, ASSIGNOR TO THE NATIONAL ELECTRICSPECIALTY COMPANY, OF TOLEDO, OHIO,

A CORPORATION OF OHIO.

VACUUM LIGHTN IN G-ABRESTER.

Specification of Letters Patent.

Patented July 18, 1916.

Application filed December 16, 1912. Serial No. 737,017.

To all whom it may concern Be it known that 1, JOHN T. GREENE, a citizenof the United States, residing at Toledo, in the county of Lucas andState of Ohio, have invented certain new and useful Improvements inVacuum Lightning-Arresters, of which the following 1s a specification.

My invention relates to lightning arresters of the vacuum ty e, and theinvention has for a primary ob ect to provide a convenient, durable andinexpensive mounting for the electrodes of a vacuum lightning arresterwhich will accurately and permanently position said electrodes withinthe evacuated vessel and at proper distances, one from another, so thatthe spark gap or gapswill not be destroyed or altered by rough handlingin shipment, or vibration and the like, when the devices are used.

A further object is to provide a mounting of the sort above indicated,which will protect the seals of the leadingdn wires from the effects ofthe discharge across the'spark gap or gaps.

The invention is illustrated in the accompanying drawings, whereinFigure 1 is a longitudinal sectional view showlng a preferred embodimentof the invention; Fig. 2, a sectional plan taken on line 2-2 of Fig. 1;Fig. 3, a view, in perspective, of the non-conducting refractory elementin which the electrodes are mounted, and Figs.

4 and 5, views, in perspective, of the electrodes.

Like characters of reference desi nate like parts in the several figuresof the drawlteferring to the drawing, 10 designates a base of refractorymaterial, such as porcelain, upon which is mounted, in any suitablemanner, an evacuated, or partially evacuated, vessel 11 preferably madeof glass. The vessel is formed preferably with an inwardly projectingglass stem 12 through which the leading-in wires are sealed. Thearrester shown in the drawing is designed for a metallic circuit andhence there are three electrodes, two line electrodes, and a groundedelectrode. 13 designates the grounded electrode, and 14, 1 1 the lineelectrodes. These electrodes are arranged in an element made preferablyintegrally, of some non-conducting, highly refractory material such asporcelaln, whlch 1s so formed and constructed as to engage theelectrodes at both ends so as to prevent all possibility ofdisplacement. The element, a detail of which is shown in Fig. 3,consists of a base 15 to which the electrodes are attached bysuitablesecuring devices, and a yoke 16 extending around and engaging the upperor free ends of said electrodes. The electrodes consist preferably 01carbon blocks and, as a matter of convenlence, the grounded electrode 13(Fig. 4) 1s formed with lugs or feet 17 which are perforated for screws18 by means of which the electrode is secured to the base 15. Each lineelectrode 14 (Fig. 5) is also preferably formed with a projection orfoot 19 perforated for an attaching screw 20. The transverse member ofthe yoke 16 is formed with a groove 21 into which the upper end of thegrounded electrode fits, and with similar grooves 22 14. The base 15 ispreferably, though not necessarily, formed with projections 23, 23intervening between the central electrode 13 and the electrodes 14 onthe other side therefor the line electrodes cured to the screw 18 andthe leading-in wires 25, 25 for the line electrodes are similarlysecured to the ends of the screws 20. The mounting structure 15, 16, maythus be supported on the leading-in wires but preferably, in order toinsure a firm and durable support for the same, I fill in the spacearound the ends of the leading-in wires and between the base member 15and the stem 12 with a body 26 of asbestos cement, or other similarmaterial, which, when it hardens, will give an additional support to theporcelain member 15, 16 and the electrodes.

In lightning arresters of the vacuum type in which electrodes consistingof blocks of carbon, or other similar material, are arranged within anevacuated glass vessel through the. walls of which the leading-in wiresare sealed, considerable difiiculty has been experienced in obtaining acheap and convenient means for mounting the electrodes which will firmlyand reliably hold said electrodes in the desired position as against therough handling which the arresters may receive in shipment and thevibration to which they may be subjected when vides means for mountingthe electrodes which meets all these requirements. The electrodes areaccurately and very firmly positioned by employment of the base member15 with its yoke 16. Each end of each electrode is positively held infixed position. The manufacture of the device is simple and inexpensive.lhe electrodes are slipped into the porcelain member 15, 16 and thescrews 18, 20, driven through perforations previously formed in thebase. The cement 26, besides holding the mounting element in position,gives an anchorage for the ends of the screws. It will be observed,furthermore, that as the base 15 intervenes between the seals of the1eading-in wires and the electrodes the former are protected as againstdirect contact of the arcs across the spark gaps.

I claim. I

1. A lightning arrester comprising an evacuated vessel providedwith aninwardly projecting stem, leading-in wires sealed through said stem, abase member Withinsaid vessel, a plurality of carbon blocks to serve thefunction of electrodes, each formed with a perforated foot, attachingdevices extending through the perforations in said feet, and throughsaid base member, with the extremities of whichsaid leading-in wires areconnected, a body of plastic, non-conducting material between said stemand said base, a yoke rigid with the base, which extends around andengages the outer ends of the carbon blocks so as to hold the same inspaced relationl 2. A lightning arrester comprising an evacuated glassvessel formed with an inturned stem, leading-in Wires sealed throughsaid stem, a base arranged above and transversely to the stem, having ayoke member thereon, both of nonconducting, refractory material,electrodes in parallel arrangement between and secured to said base andyoke and electrically connected with said leadingin wires respectivelythrou h the base, and a body of plastic, noncon ucting material unitingthe base to the stem and inclosing the'upper ends of the leading inwires.

JOHN TYLER GREENE.

Witnesses:

C. C. BREELY, P. H. CHAPMAN.

